Posts Tagged: Tom Zavortink

The European wool carder bee (Anthidium manicatum), so named because the female collects or cards "plant hairs" or "plant fuzz" to line her nest, is strikingly beautiful.

The bee is mostly black and yellow. The females, about the size of a worker honey bee, range in body length from 11 to 13 millimeters, while the males are 14 to 17 mm.

The males are very territorial. They put the "terror" in territorial. We see them hovering over the lavender in our yard and then bodyslamming honey bees. This behavior results in very skittish honey bees; no wonder honey bees don't linger on the blossoms long when their cousins show up!

The European wool carder bee, as its name implies, is a non-native. But so, too, are the honey bees, which European colonists brought to America in 1622.

The wool carder bee, according to research entomologist Tom Zavortink of the Bohart Museum of Entomology at UC Davis, was accidentally “introduced into New York state, presumably from Europe, before 1963.” It was not purposefully introduced to pollinate alfalfa, as some reports allege, he said.

Writing in a 2008 edition of the Pan-Pacific Entomologist, Zavortink and fellow entomologist Sandra Shanks, now of Port Townsend, Wash., pointed out that several papers “have documented its spread from neighboring areas in the northeastern United States and southern Canada” and that the species has since crossed the country. It was confirmed in Colorado in 2005, Missouri in 2006, and Maine, Michigan, Maryland and California (Sunnyvale) in 2007, the entomologists wrote.

Records show it was first collected in Davis on July 26, 2007.

The wool carder bee nests in convenient cavities such as old beetle holes and hollow stems, according native pollinator specialist Robbin Thorp, emeritus professor entomology at UC Davis. Its plant preferences include lamb’s ear (Stachys byzantine, in the mint family Lamiaceae), a perennial grown for its fuzzy, silvery gray-green foliage. It’s also been collected in the figwort/snapdragon family (Scrophulariacae) and the pea and bean family (Fabaceae), according to the Zavortink-Shanks research.

And in our yard, it seems to prefer three plants: lamb's ear, catmint, and lavender.

A good time to photograph the European wool carder bee is in the early morning when it's warming its muscles to prepare for flight.

It lies perfectly still.

That's what it did in our yard last weekend. It warmed itself on the sunny side of a leaf.

Not unlike the sunny side of a street...

The European wool carder bee (Anthidium manicatum), so named because the female "cards" or collects plant material to line her nest, is a relative newcomer to the United States. UC Davis research entomologist Tom Zavortink of the Bohart Museum of Entomology says it was accidentally introduced into New York State before 1963.

Writing in a 2008 edition of the Pan-Pacific Entomologist, Zavortink and fellow entomologist Sandra Shanks now of Port Townsend, Wash., pointed out that several papers “have documented its spread from neighboring areas in the northeastern United States and southern Canada” and that the species has since crossed the country. It was confirmed in Colorado in 2005, Missouri in 2006, and Maine, Michigan, Maryland and California (Sunnyvale) in 2007, the entomologists wrote.

The bee is mostly black and yellow. At first glance, its stark markings remind you of a yellowjacket. The females, about the size of a worker honey bee, range in body length from 11 to 13 millimeters, while the males are 14 to 17 mm.

The males can be aggressive in defending their territory, sometimes body-slamming honey bees and other insects to the ground.

Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, says that this kind of contact has a purpose. The male wool carder bee is "merely defending its territory from honey bees and other flying insects to keep the area free of potential competitors that might interfere with its mating opportunities," he says.

One thing's for sure: they do move fast!

Except in the early morning when they're warming their flight muscles...

When this insect flashes by you in your garden, at first glance you think: "Yellow jacket? Paper wasp? What's that?"

Then it lands and you realize it's neither.

It's a bee.

The insects buzzing in our catmint last weekend were wool-carder bees, Anthidium manicatum (Linnaeus), as identified by several UC Davis entomologists: Tom Zavortink of the Bohart Museum of Entomology; native pollinator specialist Robbin Thorp, emeritus professor of entomology, and Lynn Kimsey, director of the Bohart Museum of Entomology.

Regarding the carder bee, Zavortink teamed with Sandra Shanks, then of the Bohart Museum, to write a scientific note, "Anthidium manicatum (Linnaeus) (Hymnoptera: Megachilidae in California)," published in the July 2008 edition of the journal Pan-Pacific Entomologist.

"The Palaearctic wool-carder bee Anthidium manicatum (Linnaeus, 1758) was introduced into New York state, presumably from Europe, before 1963 (Jaycox 1967)," Zavortink and Shanks wrote. However, it wasn't detected in California until much later. In 2007, an image of a carder bee from Sunnyvale, Santa Clara County, appeared on the Bug Guide website.

The name, carder bee, comes from its behavior of gathering "down" or "fuzz" from leaves to build its nest.

"Anthidium manicatum builds a linear row of cells, each one being lined and partitioned with cottony down 'carded' from hairy leaves," wrote Christopher O'Toole and Anthony Raw in their book, Bees of the World. "The term 'carder' refers to the teasing out or carding of woollen or cotton fiber with a comblike tool. The female of A. manicatum has five sharp teeth on each jaw and these are her carding tools."

The males are very territorial, the three UC Davis entomologists agreed.

Indeed they are.

The males, about the size of honey bees, buzzed furiously around the catmint last weekend. When they spotted an "intruder," such as a honey bee, they hit it with such force (body slam!) that the victim dropped to the ground.

We also observed carding of the leaves and mating. An Indy-500 male grabbed a female foraging on a catmint blossom.